Re: [PATCH v2 3/3] dt-bindings: mfd: max8998: Add charger subnode binding

[PaweÅ Chmiel]

On Monday, July 16, 2018 12:00:03 PM CEST Rob Herring wrote:
> On Sat, Jul 14, 2018 at 02:26:53PM +0200, PaweÅ Chmiel wrote:
> > This patch adds devicetree bindings documentation for
> > battery charging controller as the subnode of MAX8998 PMIC.
> > 
> > Signed-off-by: PaweÅ Chmiel <pawel.mikolaj.chmiel@xxxxxxxxx>
> > ---
> > Changes from v1:
> >   - Removed unneeded Fixes tag
> >   - Correct description of all charger values
> >   - Added missing property unit
> > ---
> >  Documentation/devicetree/bindings/mfd/max8998.txt | 24 +++++++++++++++++++++++
> >  1 file changed, 24 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/mfd/max8998.txt b/Documentation/devicetree/bindings/mfd/max8998.txt
> > index 23a3650ff2a2..196e50097a36 100644
> > --- a/Documentation/devicetree/bindings/mfd/max8998.txt
> > +++ b/Documentation/devicetree/bindings/mfd/max8998.txt
> > @@ -50,6 +50,23 @@ Additional properties required if max8998,pmic-buck2-dvs-gpio is defined:
> >  - max8998,pmic-buck2-dvs-voltage: An array of 2 voltage values in microvolts
> >    for buck2 regulator that can be selected using dvs gpio.
> >  
> > +Charger: Configuration for battery charging controller should be added
> > +inside a child node named 'charger'.
> > +  Required properties:
> > +  - max8998,charge-eoc-percent: Setup End of Charge Level.
> > +    If value equals 0, leave it unchanged.
> > +    Otherwise it should be value from 10 to 45 by 5 step.
> > +
> > +  - max8998,charge-restart-level-microvolt: Setup Charge Restart Level.
> > +    If value equals 0, leave it unchanged.
> > +    If value equals -1, it will be disabled.
> 
> -1 is a bit strange. Why not 'not present' is disabled?
I wanted to make it work the same way, as it was in case of using it from platform_data. 
But this is good idea, to change it a bit.
So we would have:
- 0 -> leave unchanged
- property not present in devicetree -> disabled (and set to -1 - driver is expecting it)
- value from 10-45 or (5,6,7 in case of second property)
I'll update both documentation and driver parsing code (for both properties - restart level and full timeout) and send v3 version.

Thanks for suggestion.
> 
> > +    Otherwise it should be one of following values: 100, 150, 200.
> > +
> > +  - max8998,charge-timeout-hours: Setup Charge Full Timeout.
> > +    If value equals 0, leave it unchanged.
> > +    If value equals -1, it will be disabled.
> > +    Otherwise it should be one of following values: 5, 6, 7.
> > +
> >  Regulators: All the regulators of MAX8998 to be instantiated shall be
> >  listed in a child node named 'regulators'. Each regulator is represented
> >  by a child node of the 'regulators' node.
> > @@ -99,6 +116,13 @@ Example:
> >  		max8998,pmic-buck2-dvs-gpio = <&gpx0 0 3 0 0>; /* SET3 */
> >  		max8998,pmic-buck2-dvs-voltage = <1350000>, <1300000>;
> >  
> > +		/* Charger configuration */
> > +		charger {
> > +			max8998,charge-eoc-percent = <0>;
> > +			max8998,charge-restart-level-microvolt = <(-1)>;
> > +			max8998,charge-timeout-hours = <7>;
> > +		};
> > +
> >  		/* Regulators to instantiate */
> >  		regulators {
> >  			ldo2_reg: LDO2 {
>